Effects of altered responsibility, cognitive set, and modeling on physical aggression and deindividuation.

This laboratory investigation using 64 college students as subjects assessed the role of three disinhibiting variables in producing both physical aggression and an internal state of deindividuation. Altered responsibility, congnitive set, and modeling were manipulated in a factorial design, and all three variables significantly increased physical aggression. No interaction produced significant results. The increase due to altered responsibility and varying cognitions supports Zimbardo's theory of deindividuation which relates certain input variables to wild, impulsive behavior. Questionnaire data indicated that the increase in aggression was not accompanied by internal mediational factors such as reduced self-awareness. It appears that disinhibiting forces may produce increases in antisocial behavior without necessarily producing a deindividuated internal state.